Fuel water emulsion is a mixture of hydrocarbon fuel, such as diesel fuel, and microscopically small bubbles of water are encapsulated in diesel fuel. Often, a small amount of chemical additive is required to hold the water bubbles in suspension, causing the fuel water emulsion to appear milky in color. When fuel water emulsion settles, the fuel water emulsion may become semi-stable and eventually unstable where the water separates from the fuel. Free water that has separated is harmful when it resides and sits within an engine and/or fuel system causing corrosion.
Generally, fuel water emulsion is mixed in large batches and utilized as a direct replacement fuel. The fuel water emulsion may have to sit in storage containers/tanks for extended periods before it is fed to a fuel system for an engine. To maintain stability of the fuel water emulsion, these large mixed batches require a high percentage of chemical additives. Stability may be required for as long as four months. While this approach is accepted in specific fleets, over-the-road trucks suffer many drawbacks using the pre-mixed fuel water emulsion as the replacement fuel. Namely, cold engine starting is difficult to achieve, and is further implicated with time and lower ambient temperatures. Additionally, unlike a generator that operates continuously without being shut-down, trucks shut-down for extended periods of time resulting in corrosion when free water separates from the fuel. Moreover, high ratios of chemical additives (e.g., 2-3%) required for maintaining stability of the fuel water emulsion, lead to combustion inefficiencies that result in reduced fuel efficiencies and loss of power/drivability.